ChIPs were performed using approximately 0.5-1 x 10^7 CNCCs fixed with 1% formaldehyde for 10 min at room temp. RNA was extracted using Trizol. Sequencing libraries were prepared starting from ~30ng of ChIP DNA or oligo-dT purified mRNA using the NEBNext Multiplex Oligos for Illumina kit (Cat# E7335S).